diff --git a/lib/main.dart b/lib/main.dart
index 168af9cb..e9cd53b7 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -57,6 +57,8 @@ void _absorbZeroOffsetPointerEvent(PointerEvent event) {
   }
 }
 
+final ValueNotifier<bool> appClosing = ValueNotifier<bool>(false);
+
 void main() async {
   WidgetsFlutterBinding.ensureInitialized();
   _installZeroOffsetPointerGuard(); // Workaround for iPadOS 26.1+ modal dismissal bug
@@ -255,6 +257,17 @@ class _MainAppState extends State<MainApp> with WidgetsBindingObserver {
                 darkTheme: themeProvider.darkTheme,
                 themeMode: themeProvider.materialThemeMode,
                 navigatorObservers: [routeObserver],
+                builder: (context, child) {
+                  return ValueListenableBuilder<bool>(
+                    valueListenable: appClosing,
+                    builder: (context, closing, _) {
+                      if (!closing) {
+                        return child ?? const SizedBox.shrink();
+                      }
+                      return const SizedBox.expand(child: ColoredBox(color: Colors.black));
+                    },
+                  );
+                },
                 home: const OrientationAwareSetup(),
               ),
             ),
diff --git a/lib/screens/main_screen.dart b/lib/screens/main_screen.dart
index 489ba8cc..19735958 100644
--- a/lib/screens/main_screen.dart
+++ b/lib/screens/main_screen.dart
@@ -1,7 +1,10 @@
+import 'dart:io' show Platform;
+
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:provider/provider.dart';
 import 'package:url_launcher/url_launcher.dart';
+import 'package:window_manager/window_manager.dart';
 import '../../services/plex_client.dart';
 import '../i18n/strings.g.dart';
 import '../services/update_service.dart';
@@ -64,7 +67,8 @@ class MainScreen extends StatefulWidget {
   State<MainScreen> createState() => _MainScreenState();
 }
 
-class _MainScreenState extends State<MainScreen> with RouteAware {
+class _MainScreenState extends State<MainScreen> with RouteAware, WindowListener {
+  bool _isClosing = false;
   late int _currentIndex;
   String? _selectedLibraryGlobalKey;
 
@@ -97,6 +101,11 @@ class _MainScreenState extends State<MainScreen> with RouteAware {
     super.initState();
     _isOffline = widget.isOfflineMode;
 
+    if (Platform.isLinux || Platform.isWindows || Platform.isMacOS) {
+      windowManager.addListener(this);
+      windowManager.setPreventClose(true);
+    }
+
     // Start on Downloads tab when in offline mode
     // In offline mode: visual index 0 = Downloads (screen 3), 1 = Settings (screen 4)
     // In online mode: indices match directly
@@ -277,12 +286,30 @@ class _MainScreenState extends State<MainScreen> with RouteAware {
   @override
   void dispose() {
     routeObserver.unsubscribe(this);
+    if (Platform.isLinux || Platform.isWindows || Platform.isMacOS) {
+      windowManager.removeListener(this);
+      windowManager.setPreventClose(false);
+    }
     _offlineModeProvider?.removeListener(_handleOfflineStatusChanged);
     _sidebarFocusScope.dispose();
     _contentFocusScope.dispose();
     super.dispose();
   }
 
+  @override
+  void onWindowClose() {
+    if (_isClosing) return;
+    _isClosing = true;
+
+    appClosing.value = true;
+
+    // Give the UI a brief moment to settle before tearing down the window.
+    Future<void>.delayed(const Duration(milliseconds: 150), () async {
+      await windowManager.setPreventClose(false);
+      await windowManager.destroy();
+    });
+  }
+
   List<Widget> _buildScreens(bool offline) {
     // In offline mode, only show Downloads and Settings
     // In online mode, show all 5 screens